The present invention relates to a recording and readout apparatus for X-rays.
From U.S. Pat. Nos. 4,227,084 and 4,254,200, incorporated herein by reference, an apparatus is known with which, according to the principle of xerography, or charge image copy, electrostatic images of X-ray "photographs" can be produced. As radiosensitive material a crystalline bismuth oxide compound of the composition Bi.sub.10-14 X.sub.1 O.sub.n is employed therein, in which X stands for one of the elements germanium, silicon, titanium, gallium, and aluminum, and n is a number which indicates the essentially stoichiometrically measured oxygen concentration of the compound. This bismuth oxide compound has a very high X-ray absorption, and, in small layer thickness of only 0.3 mm, for example, is suitable for the recording of an X-ray image. The material has the property of storing for a long period of time in said material the electric polarization generated by incided and absorbed x-radiation if the material is not subject to any exposure. A bismuth oxide compound of this typs is also a photoconductor with dar, resistances on the order of magnitude of 10.sup.13 to 10.sup.17 ohm.cm.